Just wondering if anyones tried this yet?ĭark cutting oil contains sulphurized fatty acids, not ZDDP. I don't think the carrier oil would be a concern as once added to the motor oil it would quickly dilute and blend in but you'd be adding a good percentage of ZDDP that wouldn't cost a lot. With a show of hands, who has built over 1000 engines in the last 25 years? Anyone?Ībout 30 or 35 pages ago someone mentioned adding Dark Thread Cutting Oil as it apparently has humungus volumes of ZDDP in it. Just a little 2276 turbo/EFI engine, maybe not all that different from yours. I believe SJ rated oils were the last to have what is considered to be an adequate amount of Zn and P, about 1200ppm (parts per million) for our air cooled VW motors. Started with 'A' and with each successive improvement in oil a new letter was added. SM = the latest rating for motor oil by the American Petroleum Institute. P = chemical abbreviation for Phosphorousīoth are from the Periodic table of the elements ZDDP = Zinc Dialkyl Dithio Phosphate - an extreme pressure anti-wear additive blended into motor oil that acts as a last line of defense against metal to metal contact. Quick sort: Show newest posts on top | Show oldest posts on topĬan someone let us know what all these mean
Official 'What oil / additives should I use' topic
